Khác biệt giữa bản sửa đổi của “Charles Babbage”

* [http://www.satyam.com.ar/Babbage/en/index.html The Babbage Difference Engine]: an overview of how it works

* [http://historical.library.cornell.edu/kmoddl/toc_babbage1.html "On a Method of Expressing by Signs the Action of Machinery"], 1826. Original edition

* [http://www.cbi.umn.edu/about/babbage.html Charles Babbage Institute]: pages on "Who Was Charles Babbage?" including biographical note, description of Difference Engine No. 2, publications by Babbage, archival and published sources on Babbage, sources on Babbage and Ada Lovelace

* [http://www.ballet.co.uk/old/history_js_babbages_ballet.htm ''Babbage's Ballet'' by Ivor Guest, Ballet Magazine, 1997]